Many commercially-produced media discs (e.g., DVD-Video discs) use digital rights management (DRM) schemes to prevent unauthorized copying of content on the media discs. However, the rapid growth of the Internet and the resulting possibility of copying and dissemination of digital data have led to growing demand for ways to prevent these illegal activities and to protect copyright holders against the problems associated with pirated copies. For example, unauthorized copies can be made of an authorized distribution copy (e.g., a commercial copy) of digital data.